2 Replies Latest reply on Apr 5, 2013 5:03 AM by ramanathan.av

    ASCII - FLOAT  conversion






      I am having a problem with using the library function "atof". The compiler user guide describes the function as one which takes a pointer to a NULL terminated string as the argument and returns a double value.




      Now what I have done is this. I have a program that creates a formatted string when user inputs each character of the string one by one by incrementing an initial character pointer (say *strptr) and finally giving a carriage return which is written as '\0' (NULL) in the last location of a string. The intial value of the character pointer is stored in another pointer variable.(say *ptrval, as in ptrval=strptr when program is initiated).




      now to convert the ascii charater string that has been created in the previous sequence into a double value I use the function atof( ). eg. cval=atof(ptrval);




      the variable 'cval' is monitored in the watch window. but it is not at all getting updated. please help me find out what could be wrong? is the way I have specified the argument correct? the compiler does not provide quality information on this.




      Danke Amigos. :)

        • 1. Re: ASCII - FLOAT  conversion

          // C main line


          #include <m8c.h>        // part specific constants and macros
          #include "PSoCAPI.h"    // PSoC API definitions for all User Modules
          #include <stdlib.h>


          #define forever 1


          double MyFloat;
          char String[] = "4.123\0";


          void main(void)
           while (forever)
            MyFloat = atof(String);
            MyFloat = 0.0; // A breakpoint in this line shows that MyFloat has a Value of 4.123




          That works





          • 2. Re: ASCII - FLOAT  conversion

            @ Bob,




             Actually, I tried a similar code before & it worked.




            But in this case, suppose we give k = UART_cReadChar() ; now upon a char input RX buffer contents are transferred to k and the Buffer is also cleared.  The UART_cReadChar() function empties the buffer everytime it is invoked, which I found out after many trials. Jes wanted to share what lead me to the right method.




            This is for you - A screenshot showing atof() converted value in a watch window is attached.


            Thanks - RAM